Neural Architectures
Three hippocampal pyramidal cells, with a colour legend for soma, apical dendrite, basal dendrite and axon, and a membrane trace of the first cell.
The idea
The subtitle reads Pyramidal cells of the hippocampus. The simulation is a close view of three of them: apical and basal trees, spines on the distal branches, a descending axon, and a trace of the membrane of the first cell.
The approach
The legend at the lower right names the colours. Soma is gold. Apical dendrite is amber. Basal dendrite is a warm grey. Axon is blue-grey. Each apical tree is grown to depth 5. Each cell has four, five or six basal trees. Spines are added on apical branches past depth 2. A scale under the cells reads 50 μm. The three somata sit left, centre-forward and right.
The panel on the right is labelled Membrane Potential and follows the left-hand cell, the first of the three. The line is gold and holds 150 samples. Faint horizontal lines sit at −70, −55, 0 and 40 mV. A dashed line marks the spike threshold at −55 mV. A spike peaks at 40 mV, then the voltage drops through a short refractory period.
Under the title, three rows report that same cell. Resting potential prints the membrane voltage, which starts at −70 mV. Active conductance, in nanosiemens, is half of how far the voltage sits above −70, and is held at zero below rest. Spike rate counts spikes from the last second and prints them in hertz.
Observe starts the spontaneous current and relabels itself Pause. Stimulate steps the first cell. Propagate steps all three in order, 50 ms apart.
- Legend: gold soma, amber apical dendrite, grey basal dendrite, blue-grey axon
- Trace of the first cell: dashed threshold at −55 mV, spike peak at 40 mV, 150 samples
- Apical trees to depth 5, four to six basal trees, a scale marked 50 μm
- Stimulate hits the left-hand cell; Propagate steps the three cells 50 ms apart
Play the current build: /simulations/neural-architectures .